
Dynamic IP Version 3	15-Apr-95

If you compile bootp with the -DDYNAMIC option it will include dynamic IP code.
When a request for an IP address comes in, bootp checks the normal entrys
as it always does. If a matching ethernet entry is not found then it calls
the dynamic code to assign a new IP address from a valid range of reserved
addresses. When an address is assigned it will be added to the end of the
/etc/bootptab file (in human readable form) where it will be found next time.

Some notes:
	Dynamic IP ranges use dummy name entrys starting with ".dynamic-"
	You may have several Dynamic IP ranges (1 to 32767)
	Range numbers MUST start with 1 (not 0)
	Ranges MUST be contigious (if not, bootp won't find the others)
	Option T254 tells bootp how many host to assign from that range
	Option T253 tells bootp how to put hostname in bootptab file
		0= IP only
		1= Host name only (fail if can't lookup)
		2= Use name first, otherwise use IP (default)
	Option T250 is a string of options to be added with new bootptab entrys
	You should not assign hosts beyond the Class C range (or end of subnet)
	If no ranges are found no addresses will be assigned
	Each Dynamic IP address is check in order for existance
	Ranges can be changed without restarting bootp
	Dynamic Address will NOT overlap with existing bootp entrys (I check)
	Dynamic Address CAN overlap with other hosts not assigned from bootp

This example defines a range to start with 204.213.176.230 and assign 20
addresses (number is in HEX).
	.dynamic-1:ip=204.213.176.230:T254=0x14:T250="gw=204.213.176.100"

As addresses are assigned that will be added to the end of the file, like:
	dynamic0.ntplx.net:ha=00009406221F:gw=204.213.176.100:

Next time bootp will reassign the same address to the same machine.
Note: Currently this is 'Automatic Assignment' not true dynamic assignment.
When used with DHCP it will allow for lease, but will not remove the address

Only tested on Sparc SunSO 4.1.3 and Linux
USE AT YOUR OWN RISK

Original Dynamic IP Assignment Code Written by:
	Andrew Lindh
	NETPLEX
	andrew@ntplx.net
	(203) 233-1111

Updated: 15-Apr-95
